<form [formGroup]="form" (ngSubmit)="onSubmit()">
  <div *ngFor="let user of users" class="form-row">
      <app-dynamic-user [user]="user" [form]="form"></app-dynamic-user>
  </div>
  <button type="submit" [disabled]="!form.valid" class="btn btn-success">submit</button>
  <p>
    submit result:{{payLoad}}
  </p>
</form>
